Two cases of Japanese girls with congenital cutis laxa associated with cardiovascular abnormalities are described. Case 1: A 12-year-old girl has been under our observation from the age of 6 months. Cardioangiogram revealed dilatation of the ascending aorta, meandering of the descending aorta and the coronary arteries, coiling of the carotid and innominate (brachiocephalic) arteries, and hypoplasia of the pulmonary arteries. Case 2: A 2.8/12-year-old girl died after our follow-up from the age of 3 months. The cause of death was congestive heart failure secondary to peripheral stenosis of the pulmonary arteries. In both cases, skin biopsy revealed a decreased number of elastic fibers and an increased amount of acidic mucopolysaccharides. The same histological features were observed in the pulmonary arteries and other arteries as well. Electron microscopic findings were diffuse thinning of elastic fibers and reduced elastic content. The high blood level of elastase (167.8 micrograms/l) in case 1 may cast a light on the unknown etiology of the disease.